This invention relates to a machine for forming large round bales of fibrous agricultural crops. Our machine improves on the existing art in that the gate, through which a completed bale is discharged, can be reclosed without having to move the baler forward to obtain clearance.
Many bale forming machines exist which form fibrous agricultural crops into bales that are either twine or wire tied. For example, the U.S. Pat. No. 4,009,653 to Sacht discloses a method for forming large round bales in a machine comprising a cage-like frame having a horizontal axis and a generally cylindrical shaped baling zone. Upwardly extending machine sidewalls form the confining end surfaces of the baling zone. A plurality of serially arranged conveying elements enclose and generally define the circumferential periphery of the baling zone. Thus, the size of the baling chamber remains constant during the bale forming process. To accomplish discharge of a completed bale, the baling chamber is divided into two portions approximately along a vertically extending axis cutting plane. The rear portion of the housing is then configured to swing upward from a hinge point at the top, thereby allowing the bale to be discharged rearward.
The U.S. patent application having Ser. No. 162,372 and now U.S. Pat. No. 4,319,446 and assigned to the same assignee as this application discloses bale forming means which differ somewhat from the implementation of Sacht. Two additional rollers are added to support the bottom conveyor belts. As viewed from the side the improved system shows four rollers on which a plurality of laterally spaced belts are trained. The second and third rollers (which are respectively in the forward and aft portions of the conveyor midsection) and the fourth roller (which is at the rear of the machine) are disposed to be generally on the cylindrical periphery of the baling zone. The first roller is in front of and somewhat below the plane containing the axis of the third roller. The Arnold et al. invention improves on Sacht in two ways. First, the vertical dimension of the entrance throat is enlarged. This allows the baler to operate in a heavier stand of hay without becoming clogged. Second, by lowering the placement of the front roller, a pickup reel of smaller diameter can be used. This permits the flow of hay being picked up from the windrow to pass into the baling zone without undergoing abrupt changes in direction. The laterally spaced conveyor belts accept the crop material being passed on from the pickup reel and frictionally engage the crop strands to provide inward directed pressure to carry them into the baling zone.
This invention is shown in conjunction with a baler having a bottom conveyor member for receiving agricultural material which is constructed similar to that disclosed in the U.S. patent application having Ser. No. 162,372. Using this type of bottom conveyor, generally cylindrical bales are formed in a cavity of fixed size. The partially completed bale rotates on a horizontal axis while crop material picked up from a windrow is continuously added to the periphery of the bale. As the baling chamber fills, pressure is exerted on the surrounding enclosure. The enclosure is hinged along the front edge to allow the upper portion to open from the rear like a clam shell to enable discharge of a completed bale. A latch mechanism holds the opposing faces of the enclosure together until the bale is complete.
With our invention discharge of the completed bale is accomplished in a way which improves on Sacht. With the Sacht teaching, the rear portion of the baler housing swings upward from a hinge point at the top. Discharge of the bale leaves it under the overhanging raised portion of the tailgate structure. Before the tailgate can be closed, the operator has to move the baler ahead some eight or ten feet to allow the raised structure to clear the bale which is lying on its side on the ground. Since the baler has to be moved ahead to allow the tailgate to be closed, the operator of the Sacht machine goes through a sequence as follows. He stops his forward process along the windrow when a bale is formed. He then shifts the tractor into reverse, backing the baler up ten feet or thereabouts. The bale is then discharged and the tractor placed in forward drive. After driving ahead a few feet to enable the raised structure to clear the bale, the tractor clutch is then depressed and the tailgate of the baler closed. With the tailgate closed, the baler is ready to resume forward progress along the windrow.
Using our improved baler, the operator does not have to backup his machine to discharge a bale. The discharged bale does not prevent immediate closure of the tailgate since it is not deposited on the ground in an area which is under the overhanging raised structure. This ability to immediately close the tailgate saves time as well as wear and tear on both the tractor and the operator.